A member of Pres. Barack Obama’s own party is casting doubt on whether the president’s financial regulation overhaul goes far enough, particularly when it comes to hedge funds.

Obama’s plan lets hedge funds off relatively easily, for now, proposing only mandatory registration with the Securities and Exchange Committee and vague hints about giving the Federal Reserve the power to regulate “systemically important” financial firms. But Luis Aguilar, a commissioner on the SEC, believes more is needed.

“It seems certain regulation for hedge funds is coming,” he told a HedgeWorld conference yesterday.

Simply requiring registration doesn’t go far enough, Aguilar, who was appointed by former Pres. George W. Bush last year, said. He said that certain parts of the 1940 law that regulates mutual funds should be applied to hedge funds, and that the biggest hedge funds—those most likely to be systemically important—should face stricter rules, including leverage limits.

Aguilar also said that lawmakers and regulators should revisit the definition of “sophisticated investor.”

“These sophisticated investors may not have fully appreciated the risks they were taking prior to the recent crisis,” he said. “Perhaps the definition of ‘sophisticated’ should be reconsidered. Maybe the criteria should focus on actual investment experience, not just net worth or income.”